Series / Behind the Rack

Behind the Rack

15 articles on what keeps your website's server running, one layer at a time.

A data centre is, at heart, a very large and very well-organised electrical installation. Power arrives from the grid...

Nearly all the electricity that goes into a server comes out again as heat. A single rack of ordinary servers can put...

A hosting provider's connection to the internet is not a single cable. It is a set of links to several upstream...

Hard drives fail. That is a statistical certainty, not a rare accident, and storage design starts from that assumption....

A facility that stores other people's websites and customer data is serious about who can get in. Typical measures...

Spare parts do not prevent every outage, because many outages are not caused by parts. Three examples that have been...

Servers are mounted in standard-width racks, measured in rack units of 4.4 centimetres. A typical rack has 42 of them....

Water sprinklers and electronics are a poor combination, so data halls often use other methods. Very early smoke...

When a disk fails in a server hundreds of kilometres away, somebody has to walk to the rack. Data centre staff provide...

A data hall is full of sensors: temperature and humidity at rack level, power draw on each circuit, water leak...

A hosting provider reaches the rest of the internet in two ways. It buys transit from larger networks, which carry its...

Most hosting today runs on virtual machines or containers. A hypervisor divides one physical server into many virtual...

Many outages begin with a planned change. Serious operators therefore treat changes carefully: peer review, tests in a...

A disaster recovery site is a second location able to take over if the first is lost. It can be a hot standby, running...

Data centres use roughly one to two percent of the world's electricity, and the figure is growing as more computing...